Telephone-exchange system.



C. W. KECKLER.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAY24. I917.

Patented Aug. 27, 1918.

I UNITED STATES TPATE'NT OFFICE. 1

CHARLES w. KECKLEROF NEwAnK, nnw JERSEY, nssrcnon T0 WESTERN nnnc'rnrcCOMPANY, mconronA'rnnor NEW YORK, n. Y., A conronerron on NEW YORK.

TELEPHONE-EXCHANGE SYSTEM.

Specification of Letters Patent.

Application filed May 24, 1917. Serial N 0. 170,603.

and useful Improvements in Telephone-Exchange Systems,of which thefollowing is a full, clear, concise, and exact description. Thisinvention relates to telephone exchange systems, and more particularlyto such systems of'the central energy type.

While it has been recognized that itis desirable'to provide means bywhich a subscriber, connected with a central oifice link circuit, might,under certain circumstances, attract the attention of the central officeoperator without the necessity of repeatedly moving the switchhook upand down, the

means provided for obtaining this objecthas resulted in confusion ofsignals to the operator, It is well known that a subscriber initiating acall causes the continuous operation of a line signal, which signal'isan indication to the operator that some action upon her part, for thebenefit of the subscriber, is

called-for. In the systems heretofore used,

" the attention ofthe operator is attracted by a connected subscriberthrough'theintermittent operation of the supervisory signal. It "will beseen, therefore, that the continuous operation of the line signal andtheintermittent operation of the supervisory signal are bothindicationsto the operator that some 'actnpon} her part, for the benefit of thesubscriber, is called for, a'nd,.therefore, some confusion results.Itflis the object of the present invention to avoid this confus on,

and to provide a system in which all the benefits derived from thesystems heretofore used are retained.

- In accordance 'with a feature of this invention, the supervisoryslgnal of a link circuit, when connected with thetelephone line, iscontrolled over the telephone line and is intermittently operated ,tofurnlsh a dis- "connect signaland continuously operated to I furnish arecall signal." This continuousoperation of the supervisory. relay tofurnish "a recall indication isfan' indication of the same character asthat furnished by the conboth are indications to the operator that someacton her part, for thebenefit of the cation calling for an act for thebenefit of the subscriber, may, therefore, very properly be of adifferent character from the recall indication.

In accordance with another feature of this invention, should the linkcircuit be connected with the telephone line as a calling line and'thelistening keybe in its normal position, the supervisory signal will becontinuously operated to serve as another in- Patented A110. 27, 1918. I

dication to the operator that an act on her indication is theintermittent operation of av signaling device. In this way all confusionofsignals is avoided.

For a-more complete understanding of this invention, reference should behad to the following description, taken in' connection with theaccompanying drawing, wherein is shown a telephone exchange systemcontaining one embodiment of the invention. I j

7 All apparatus is shown in its normal'and .unactuated condition, It isbelieved that an understanding of this invention may be gained from adescription of the operation of the systems disclosed in the drawingsand it will'be so described.

.Therezare shown two telephone lines phone lines The subscriber A, ininitiating a call, ca'uses the. lighting ofv the usual line lamp 5, andthe operator, observing the light-1 ed condition of this'lamp, answersthe call by inserting "answering :plug 6 of the cord circuit G into linejack 7 whereuponanswering 'supervisorylamp 8 is lighted and cutoffrelayn9 isqoperatedover a circuit from battery-through lamp8, resistance10, sleeve contacts of answering'plug. 6-,and line jack Y 1 7, andthewinding of cutoff relay .9 to

ground. The operation of the cutoff relay .9 disconnects line relayllfrom the tele- "phoneline A. 7 Upon the connection .of the answeringplugof the cord'circuit withthe Y 5 line jack of the telephone 1ine,.relay's15 and 1110 16 are operated over a circuit from battery through inding17 of "repeating -coil- 18,

Winding of relay 15, ring contacts of the answering plug 6 and the linejack 7, over one side of the line, through the "station apparatus, backover the other side of the line, tip contacts" bf theline ack 7 and theanswering plug 6, Winding 19 otrepeating coil 18, Winding of relay 16,and normal contact of'relay 20 to'gl'OllllCli The operationot relay 15wvould connect aresistance 21 in shuntivith the lamp SWBIG-lbIlOt forthe fact that relay 16 is operatechbutsince relay 16 is now actuated,the answering supervisorylamp 8 remains lighted to furnish a continuoussignal indicatingto the operator thatsoine act upon her partzfor thebenefit of the subscriber is-required. Theoperator inay'noiv actuatelistening key 22 to connect theoperators telephone set to the cordcircuit. A-c'ontac't 23 iscompleteduupon the actuation of the key 22,thereby completing a circuit for and causing-the operation of relay 2O,Wl11Cll, n operatingyreleases relay 16 and completes for itself alocking circuit, including its alternatecontact. The release of relay 16connects resistance 21 inparallel 'i'vith'the lamp S, thereby'efiacingthe lamp.

The operator, upon being advised of the number or the line with whichconnection is desired, for example, line Byrestores' the listening key22 to normal position and connec'ts the calling eiid olfacord circuit C:With line'Bl The subscriber on line B maybe signaled in any desiredmanner; In responding, the called subscribervremoves the receiver fromth'eiswitchhook, thereby causing the operation ofcallingssupervisoryrelay30.

1 At tllGCOllGlLlSlOlL ot' the "conversation,

1 subscribers A' and B restoreithei-receivers to the sivitchhooks. Therestoration of the re- Lceiver to the sivitchhook by subscriberwB causesthe denergization of supervisory relay-'30. Tl161eStO1ELt1OIl to theswitchhook I of the receiver by subscriber A causesfthe de-'energization ofrelays 15 and 20, whereupon I the interrupter32-aii'd-resistance 2l are'con- 1 :nected in pai'allelxivith the lamp 8.-Due to listening key 22 to connect the operators 'telephone set :to thecord 'circuit,and in so 'doing causes the. energ'izati'oir' of relay 20and the deenergization of relay 16. Upon beingndvisedof the connectiondesired by the calling subscriber, the connection may be" established inthe manner heretofore described.

'What is claimed is: 1. A telephoneexchangesystem comprisingatelephoneiline, a link circuit connected therewith, asupervisorysignaling device, a

supervisory relay and a secondary relay for the link circuit, aninterrupter broughtinto circu t relation with the signaling. device1113011 the de'e nergization of the supervisory and secondary relays tocause the intermittent operation of the supervisorysignaling devicetofurnish a disconnect sigiial,-and an operating circuit: forthesupervisorysign alingdevice rendered eflectiveuponthe'subsequentenergization of the supervisory re- 1 lay While thesecondary relayis deiiergized to cause the continuousoperationof-thesupervisory signaling device to furnisha recall signal. I

2. A telephone exchange system comprising a telephone line, alinkcircuit, a,signaling device for the link circuit, an -operat ingcircuit forvthe. signaling device established coupon; connection of thelinkicircuit rwith -the telephone line as -a calling'line to cause theoperation ofthe signaling device, an operators telephone set, alisteningkey for-- connecting :theoperators telephone set With'the link circuit,arelay responsivetothe actuation of: the key ifori stopping -theoperationof thewsignaling device,--a supervisory I relay'for the linkcircuit, and an intermititentlyclosed operating circuit: forthetsignaling device established upoI'r the deiierj ti f th sipervisory' relay to causethe intermittent operationofsthe-isignalingdevice. I t V I I 3. I A wtelephone exchangesystem-comprising a i telephone dine, a link circuit, sig- #7, d'esireto' initiate another: call, the mere reinoval of thereceiver: from theswitchhook causesvtheoperation otirelays -1-5-and16,-

6 0 i vhich disconnects the' 'interrupter (from the w cirouitand'perniits the continuous operation roftthe'supervisoryilainp 8, whichis air-indicati'o'n to the operato tthattan act upon: her part, for the"benefiton? the subscriber, is. re-

d b 'quired. The operatormay'noiv actuatethe naling device establishedupon connection of the linkvcircuit with the telephone l-ine as acalling line to cause theoperation of the signaling device an operatorstelephone set, a listening switchkfor connecting-theori- :er-atofistelephone set With-the link circuit, a

relay respbnsive tothe actuation: ofsthe --s vitch for 'stoppingvtheoperatioiiof the signaling device, a supervisory; relay for: the linkcircuit, and anint'ermittently clo'sed- 0p- -.erating: circuitforthesignaling device established upon? the :deenergization or thesupervisory relay and the :firstnmentionedre- I lay to cause: theintermittentioperatiomof the signaling device.

4:- A telephone eXchange systenr comprising a telephone 1 line, i a link:circuit,"- signal- 1 ing device er-rte link circuite: an operating.circuit for the signaling device established upon connection of the linkcircuit with the telephone line as a calling line to cause thecontinuous operation of the signaling device, an operator controlledswitch, a relay energized upon the actuation of the switch for stoppingthe operation of the signaling device, a supervisory relay for the linkcircuit,

and an intermittent operating circuit for the signaling deviceestablished upon the de energization of the supervisory relay to causethe intermittent operation of the sig naling device to furnish adisconnect signal.

5. A telephone exchange system comprising a telephone line, a linkcircuit, a signaling device for the link circuit, an operating circuitfor the signaling device established upon connection of the link circuitwith the telephone line as a calling line to cause the continuousoperation of the signaling device, an operator controlled switch, arelay energized upon the actuation of the switch, a shunt circuit forthe signaling device established upon the actuation of the relay to stopthe operation of the signaling device, a supervisory relay for the linkcircuit, and an interrupter included in the shunt circuit upon thedeenergization of the supervisory relay to cause the intermittentoperation of the signaling device to furnish a disconnect signal.

6. A tele hone exchange system comprising a telep one line, acord'circuit, a supervisory lamp for the cord circuit, an operatingcircuit for the lamp completed upon connection of the cord circuit withthe telephone line as a calling line to cause the continuous glow of thelamp, an operators telephone set, a listening key for connecting theoperators telephone set with the cord circuit, a relay energized uponthe actuation 01. the listening key, a shunt circuit for the lampestablished upon the energization of the relay to efiace the lamp, asupervisory relay for the cord circuit, and an interrupter includedinthe shunt circuit upon the deenergizatlon of the supervisory relay tocause the intermittent glowing of the lamp.

7.'A telephone exchange system comprising a telephoneline, a cordcircuit connected therewith, a supervisory lamp for the cord signal.

In witness whereof, I hereunto subscribe my name this 22nd day of May A;D., 1917.

CHARLES W. KEOKLER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, 13.0."

